Ever since their discovery, adenoviruses have proven to be tremendous asset to biologists. Through the study of the adenoviruses the authors have learned not only about the virus structures, mechanisms of viral replication, but also about eukaryotic gene expression, alternative splicing, regulation of cell cycle progression, and apoptosis. In the last five years, there has been an explosion in the use of adenoviruses as vectors for gene transfer to a variety of mammalian cells. Adenoviral vectors are also being tested in Phase I clinical trials for cystic fibrosis and for many kinds of cancers. These recent developments in utilizing adenoviral vectors for gene therapy have rejuvenate an interest in the basic science of adenovirus research. More importantly, it has generated a necessity for a single volume that covers both the biology of adenoviruses as well as our progress in the use of adenoviruses as vectors for gene therapy. This book was written precisely to fulfill such a need.